The present invention relates generally to rotating disks and, more specifically, to improved disks that provide spatially stabilized emblematic images which are viewable when the body to which the disk is attached is stopped or moving.
For decades, manufacturers have faced the problem of advertising their products with logos on the products themselves. Perhaps in recognition of the problems or ineffectiveness attendant upon putting logos on disks, as for example, phonograph records, manufacturers have now tended to dispense with logos. One problem with using rotating disks to display a logo is that the logo can become indiscernible when the disk is moving, particularly at moderate to high speeds. Furthermore, even when the disk is moving at very low speeds, the rotation of the disk, and thus the emblematic logo, produces a blurred or rotating image that is not highly desirable. A specific example is the difficulty of reading the label of a phonograph record as it is rotating on a record player. As such, a logo on a rotating disk has provided advertising benefits essentially only when the body to which the disk is attached has stopped, so that it can be viewed by someone directly facing the disk.
Holography has provided a means not only of providing a truly three-dimensional image but also the possibility of animation of these images. The combination giving a full three dimensional image with motion (a 3-D movie) is possible just by making each frame of a movie a true hologram (see for example, paper by Metherell, et al. in Acoustical Holography, Vol. 5, by Philip S. Green). Each frame has the standard viewing limitations of a standard hologram and has the same holographic construction limitations of a standard hologram.
There are stereographic movies which exhibit a pseudo three-dimensionality but do give motion with nearly the effectiveness of a hologram since the eye (or two eyes of the viewer) only sees depth as a horizontal function only. Similarly lenticular screen stereograms can give both the appearance of three dimensionality and apparent motion.
There is a holographic technique which combines some of the aspects of stereo viewing and lenticular screen viewing. Holograms of this type were perfected by U.S. Pat. No. 3,515,452 to R. V. Pole, issued Jun. 2, 1970. In a so-called multiplex hologram, a standard camera provides a series of photographs of a three dimensional scene or subject which is either rotating or moving with respect to the camera such that a different aspect is covered in each picture. Each photograph is effectively from a different angle. A hologram is made by projecting each frame (of the two-dimensional movie or still) through a cylindrical lens onto the holographic film. Each frame forms a hologram of the two-dimensional movie frame in a narrow slit. As the hologram is viewed, each eye sees a different holographic view of the two-dimensional object and a 3-D stereogram/hologram is seen. These holograms can either be viewed flat with motion of the viewer's head providing motion (as in the lenticular screen devices) or as a rotating cylinder.
Even though the viewing time (or amount of motion before repeat) is limited for this multiplex hologram and the parallex or three-dimensionality in the horizontal axis only, a three-dimensional image with motion can be viewed.
The present invention is of another format for viewing a three-dimensional image which can, if desired, have motion included.
A need still exists in the art to provide a disk that can produce a substantially nonblurring image of a logo that remains stationary relative to the rotation of the disk.